Resume DNS tests suspended after T

5 DNS tests were suspended on T+ devices because 3 Netd binder methods
they used were moved to the mainline module and no longer being
supported by Netd. To resume tests, this commit reimplements those
firewall methods in test utility.

Resumed tests:
- BlockDnsQueryWithUidRule
- GetAddrinfo_BlockDnsQueryWithUidRule
- EnforceDnsUid
- BlockDnsQueryUidDoesNotLeadToBadServer
- DnsWithVpn

Bug: 227159929
Test: atest resolv_integration_test
Change-Id: I459c1f1c79eb8caf5bab9092c27cab3a94db106e